1. Field of the Invention
The present invention relates to the field of color images, color image media and color image processes using light emitted into a media to provide light intensity.
2. Background of the Art
There are many imaging technologies that provide color images or color viewable material with the light energy illuminating, highlighting or energizing distributed image content. The simplest such image displays are arrays of lights in patterns (especially of colors) that provide an image when viewed from an appropriate distance. Shaped neon light displays are an example of that technology. Motion pictures and slide shows are merely reflective surfaces onto which patterns of colors are projected and reflected off the surfaces for viewing. Cathode ray tubes are distributions of phosphors that emit specific wavelengths of light when irradiated (e.g., with electron beams) such that when a screen containing arrays of phosphors is irradiated in predetermined patterns, individual patterns of colors combine to form a relatively full color image that is emitted from the screen.
U.S. Pat. No. 4,497,860 (Brady) describes sheet articles having on one surface thereof a linear prism array and a diffraction grating on the opposite surface. These arrays of prisms are deformable and the sheet articles are suitable for the preparation of projection transparencies. By local deformation of the prism, the transmittance properties of the sheet articles are altered, providing differentiation in image density with transmitted (e.g., from back lighting) light.
U.S. Pat. Nos. 4,906,070 and 5,056,892 (Cobb) describes a thin, flexible film made of a transparent polymeric material including a structured surface and an opposite smooth surface, wherein light striking either surface, within certain angular ranges, is totally internally reflected. The structured surface includes a linear array of miniature, substantially right-angled isosceles prisms arranged side-by-side to form a plurality of peaks and grooves. In addition, the perpendicular sides of the prisms make an angle of approximately 45° with the smooth surface, and when the film is curled the smooth surface lies in a smooth continuous arcuate curve without materially affecting the performance of the film. Because of the film's flexibility and its ability to totally internally reflect light, it may be utilized in a variety of ways, for example, as a collector of solar energy or as a light conduit. The performance of the film may be manipulated to permit controlled light leakage.
U.S. Pat. No. 5,919,551 (Cobb et L.) describes a structured optical film with variable pitch peaks and/or grooves to reduce the visibility of moire interference patterns and optical displays incorporating one or more layers of the film. The pitch variations can be over groups of adjacent peaks and/or valleys or between adjacent pairs of peaks and/or valleys.
U.S. Pat. No. 5,949,346 (Suzuki) describes an LED display device with an indicator having a housing. The housing has at least one incident portion that receives light from at least one LED. The incident portion has a reflection surface at its inside surface. LEDs emit light from one side or one longitudinal end of the incident portion. A refraction-plate may be provided to direct emission of the incident light for viewing by a user.
U.S. Pat. No. 6,356,389 (Nilsen et al.) describes a light collimating film having a first side and a second side, wherein the first side includes a series of prisms, and the second side includes a plurality of sub-wavelength optical microstructures. Another embodiment includes a back-lighting display device having a lighting means, a display print, and a sheeting having a first side and a second side, wherein the first side includes a series of prisms, and the second side includes a plurality of sub-wavelength optical microstructures. A preferred embodiment includes a back-lighting display device having a collimating film with a first surface having a sub-wavelength optical microstructure thereon and a second surface with linear prisms having an included angle of greater than about 95°, and a second collimating film having a first surface with a sub-wavelength optical microstructure thereon and a second surface with linear prisms having an included angle of less than about 85°.
Alternative imaging structures and technology are still desired. All disclosures cited in this patent are incorporated in their entirety herein.